learn as you go

grouchyolfart · #21 (**permalink**) 07-05-2009, 04:41 PM

If it's the same I've been seeing around, expect it to cost around $200, give or take a few.

deacon · #22 (**permalink**) 07-05-2009, 05:22 PM

Quote:

Originally Posted by grouchyolfart

If it's the same I've been seeing around, expect it to cost around $200, give or take a few.

Way out of my range... I can build my trailer for about fifty at the very most. Pick up a 16 bike for five bucks at a yard sale and couple of pieces of scrap metal and you are there. Course it won't be as purdy... Heck I can buy a real trike for 250

deacon · #23 (**permalink**) 07-09-2009, 10:21 PM

My newest pusher turned out to be a bust. I was using the kid's bike wheel and somehow the bearings were bad. The wheel locked up.

I tried to reuse the sprocket which I had welded to the bike sprocket and it got warped. So the second version wasn't any better than the others. That time the chain wouldn't stay on. So now I have decided to look at friction drive again. This time with an electric motor and a scooter wheel or maybe a lawnmower wheel with a sprocket attached.

I know I promised that I was not going to build a new bike but technically I'm not. I am just repairing the last one. Or I'm still working on the last one.

deacon · #24 (**permalink**) 07-10-2009, 10:12 PM

I have always pushed out the pin on a bike chain and then reset it when I resized the chain. However I have also spent about a hundred bucks of chain breakers. Two bike shop parks and a half dozen bell. So I have just begun grinding them down and using master links.

I also general turn a junker mountain bike into a single speed. I was doing that today when I used a coaster master link on it. I got some serious chain noise on the first test run. I think I have figured out how to get rid of the noise. I'll probably have to adjust the chain again. If the master link clip faces away from the gear nest it should be okay. I Think the safest way to do it is clip on the outside of the bike. Biggest sprocket in front and match it to the straightest chain run in the rear. If you have a better idea let me know..

deacon · #25 (**permalink**) 07-11-2009, 06:00 PM

Learn as you go does pay off...

I made a friction drive bike complete in one day. Lessons from the old ww bikes and from the pusher made it possible. Most of the developmental work was done. It was just a matter of adapting it. I do have to finish wiring it and finish the trailer for the batteries to test it with but that's all there is left. I could do it tonight but I'm tired.

deacon · #26 (**permalink**) 07-12-2009, 02:08 PM

But it looked so good...

The friction drive was just way way too slow. That had to do with me trying to run it with the sprocket from a scooter instead of direct drive from the drive shaft of the motor. Oh well another lesson learned. I had a feeling last night that it was going to run very slowly. Sometimes I hate to be right.

I went from 11 teeth on the motor to 44 teeth on the drive wheel. Probably cut the rpms at least by 75%... I am going to change the whole thing to a ride to the park bike. That's tomorrows project today is family day. I have to shower and play grandpa...

deacon · #27 (**permalink**) 07-13-2009, 02:20 PM

I have no idea what I did or how long it will work but I have managed to build a really nice little bike. I went back to the pusher design after the friction drive fiasco. I managed to attach a sprocket to the front wheel of a 16 inch kids bike. It doesn't have a freewheel so I expect it to wear the motor out pretty fast. There might be an unexpected advantage but I'll have to check to see. I am told that if you run a brushed motor and the motor turns faster than your demand for power, ie downhill coasting, that the motor becomes a generator. I'm not sure if this controller will allow the current to back flow to the batteries or not.

I am using 1 350 watt motor with a #25 chain drive. I think there are 11 teeth in the motor sprocket and 67 in the wheel sprocket. It isn't as fast as the 44tooth rear sprocket with the 500 watt motor but it is respectable. With the combination I have, it will not allow me to pedal 90% of the time. It has to be a really long or steep hill to wind down slow enough for me to catch up to the bike freewheel.

I put it on a small 20" frame with a suspension front end. It rides good and it pedals good. I have a coaster rear wheel and I like those. I think from now on I will try to use coaster rear wheels when ever I can find one. Actually the old three speed wheels would be good except for the size of the tires.

My one big learning experience this time is to bolt and WELD all the joints.

deacon · #28 (**permalink**) 07-16-2009, 11:10 AM

I have known this for sometime but it is much easier to build it right the first time than try to patch it together. That said seldom do I know the right thing to do till I have done it at least ten times wrong.....

Stubby79 · #29 (**permalink**) 07-18-2009, 12:48 PM

Deacon, may I ask the specifics of what you're running on this build? if not...
What voltage are your motors?
What size batteries (amp-hours), how many and in what configuration(parallel or series) are they?
What size wire are you running, and how long?
What kind of switch or motor controller are you using?
What's the range on your latest configuration?

Let me know...2 miles might be a good or poor range, depending on how many batteries of what size are being used.

deacon · #30 (**permalink**) 07-18-2009, 03:40 PM

Ah the configuration that gets me to the park for my walk(two miles with less than half the battery left) is a pusher trailer with a 16" bicycle wheel and a 67 tooth rear sprocket. It is powered by a 350 watt 24v currie motor. The batteries are (2) 7.5 ah 12 volt in series. I left the house with 13.25v on them and come in with 12.4 volt per battery. They are probably good for another mile, maybe more, but the performance goes down at about that level usually. Ie more and harder pedal assist. The bigger bikes have more ah and bigger motors.

The controller is 24v 350 watts...... The wiring is 14guage with a house type wall switch as the kill switch. Real ghetto stuff...